Automatic firing pneumatic hand tools such as staplers and nailers have been in use for some years. In such tools, generally the main valve controlling the access of air to the piston is pneumatically operated by a remote valve which is trigger actuated. The remote valve operates within a reciprocable sleeve. By means of a setting of the selector valve the sleeve may be caused to reciprocate so that as the trigger is held in its depressed condition, the reciprocation of the sleeve will produce an auto-fire mode of operation.